In U.S. Pat. No. 2,838,778 issued to Von Arx in 1958 apparatus for cleaning the inside and thee outside of pipe is disclosed. However, the assembly for cleaning the interior of the pipe is complicated and expensive.
U.S. Pat. No. 3,436,783 discloses an apparatus for cleaning the interior of pipe. This apparatus is portable.
U.S. Pat. No. 4,433,448 discloses apparatus for cleaning the exterior of pipe and apparatus for varying the diameter of the brush assembly to treat the pipe.
U.S. Pat. No. 4,166,301 discloses brushes for treating the exterior of the pipe and a scraper or blade with a plurality of cutting edges rather than brushes to clean the interior of the pipe.
U.S. Pat. No. 4,372,003 discloses a portable unit for treating both the outside of treaded and the inside, but the apparatus does not allow the simultaneous treatment of both the inside and the outside of the pipe.